Volumetric ultrasound scanning of the breast may be used as a complementary modality for breast cancer screening. Volumetric ultrasound scanning usually involves the movement of an ultrasound transducer relative to a tissue sample and the processing of resultant ultrasound echoes to form a data volume representing at least one acoustic property of the tissue sample. Whereas a conventional two-dimensional x-ray mammogram only detects a summation of the x-ray opacity of individual slices of breast tissue over the entire breast, ultrasound can separately detect the sonographic properties of individual slices of breast tissue, and therefore may allow detection of breast lesions where x-ray mammography alone fails. Further, volumetric ultrasound offers advantages over x-ray mammography in patients with dense breast tissue (e.g., high content of fibroglandular tissues). Thus, the use of volumetric ultrasound scanning in conjunction with conventional x-ray mammography may increase the early breast cancer detection rate.
In one example, a full-field breast ultrasound (FFBU) scanning apparatus may be used to image breast tissue in one or more planes. One side of an at least partially conformable, substantially taut membrane or film sheet compresses the breast. A transducer translation mechanism maintains an ultrasound transducer in contact with the other side of the film sheet while translating the ultrasound transducer thereacross to scan the breast. Prior to initiating the scanning, a user of the scanning apparatus may place the ultrasound transducer on the patient tissue and apply a downward force on the transducer to compress the tissue in order to properly image the tissue. However, the user may become fatigued and decrease the pressure applied to the scanning apparatus as the scanning progresses, compromising the quality of the acquired images.